There's nits on your nits: most residents (citizen or otherwise) don't own their properties; and while these things do work with houses, they are intended for apartments.
Most of them are installed by tenants. Who also aren't all citizens, so you aren't wrong there. Maybe "Germany's resident's" would be more accurate, but of course some small percentage will be installed by landlords who actually reside abroad. You will never get that title to be 100% accurate
